# Columns From CAD

This command creates structural columns from linked 2D CAD files, it reads the closed rectangles and circles on the selected layer and restricts to the heights of the specified levels

![The Structural Columns From CAD Dialog Box.](/files/-LgvYWA4q8X4oua4YfC_)

**Rectangular Family:** When Onbox detects a Rectangular Shape Geometry, this Structural Column Family will be used for creating the Instances.

**Circular Family:** When Onbox detects a Circular Shape Geometry, this Structural Column Family will be used for creating the instances.

**Layer:** The layer of the CAD reference that will be used for detecting the geometry.

**Levels:** You can specify which Levels will be utilized for creating the Columns.

![](/files/-Lgv_P5Cy2ocCuEehGsE)


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